Potassium acrylate copolymer and agave fiber as improvers of stone substrates for greenhouse production

Success in greenhouse production is due, in part, to the use of a well-characterized substrate and a suitable fertigation schedule, among others. The behavior of several mixtures of stone substrate (tezontle, pumice) with improvers (potassium acrylate copolymer and agave fiber) was evaluated in this research. The physical properties of the resultant mixtures, such as water- and air-retention, drainage and apparent density. Were measured and then, the energetic state of the mixture (Field Capacity (FC)) was calculated in laboratory. Afterwards, the mixtures were exposed to irrigation in greenhouse conditions; the FC and drainage were measured. T-3 (pumice with 8g of potassium acrylate copolymers) and T-6 (pumice agave fiber) were distinguished by having a favorable moisture retention, T-1 (pumice) was selected as control. These treatments were carried in a greenhouse cucumber crop cycle.